Sound amplifier



Sept. 3, 1929. A. sEu=ERT SOUND AMPLIFIER Filed March 29,' 192e 2Sheets-Sheet 1 Erwan/Coz attain?? Patented Sept. 3, 1929.

UNITED STATES PATENT OFFICE.

ANTHONY SEUFERT, OF ALBUQ'U'ERQ'UE, NEW MEXICO.

SOUND AMPLIFIER.

Application mea March 29, 1926. serieu No*- 98,203.

thereof are such as will permit the stylus of the sound box to cooperatewith all makes of disc records.

As is well known, the sound groove of one make of disc record has itsbottom surface undulated, so as to cause vibrations to the diaphragm ofthe sound box throughthe medium of the stylus, while the side walls ofthe soundv groove of another make of record have the undulations,causing lateral movements to the stylus and thus creating lateralvibrations to the diaphragm of the sound box.

With these facts in view, another purpose of the present invention is toprovide, in a sound amplifier, what is known as a tone arm portion whichwill permit the stylus of the sound box to cooperate with these twoconstructions of records by simply twisting` certain portions of t-hetone arm, so as to allow the stylus to play in the sound groove.

Still another purpose is to provide, in a sound amplifier, a pliable capor sound defiector to be fastened on the face of the sound box in orderto deflect all the sound back through the tone arm, which is continuousfrom the sound box to the outlet terminus of the amplifier, hencereproducing the human voice in a loud, clear, broad effect with volumeand sonority unequaled by other constructions.

rlhe invention comprises further features and combinations of parts tobe hereinafter set forth, shown in the drawings and claimed.

In the drawings:

Figure 1 is a view in section of a talking machine cabinet, showing theimproved amplifier and its tone arm section as applied, the stylus ofthe tone arm section operating upon a record which causes lateralvibrations of the stylus.

Figure 2 is a plan view of the cabinet showing a record on theturn-table, illustrating the amplifier applied with its tone arm sectionin elevation and its outlet terminus portion in dotted lines.

Figure 3 is a sectional view of a talking machine cabinet with theamplifier applied, the tone arm cooperating with a record which impartsvertical vibrations to the diaphragm of the sound box.

Figure 4 is a horizontal sectional view of Figure 1, taken just belowthe plane of the sound board.

Figure 5 is a sectional view on the plane indicated by the line 55 ofFigure 1.

Figure 6 is a detail sectional view through the sound box, showing therubber sound defector.

WVhile, in the illustrated embodiment of the invention, its applicationis shown in connection with a talking machine, it is obviouslyapplicableto radio in connection with loud speakers or wherever megaphonic soundsare desired. A portion of the talking machine cabinet 1 is illustrated,being provided with what is commonly called a top-plate 2, this lattersupporting the amplifier 3 and particularly the tone arm section 4thereof. The amplifier comprises an amplifying section proper 5 which ishoused in the cabinet, including an elbow 6 which telescopes anextension 7 of a sleeve 8.

, The sleeve 8 is carried by the top-plate 2 and the extension 7 passesthrough the board, there being an annular flange 9 on the sleeve whichreceives fastening means 10 to secure the sleeve to the top-plate. Theelbow 6, as previously stated, telescopes the extension 7, there being arubber gasket 11 to insure a close fit and prevent the escape of soundand to insure full vibrations of the cabinet as well as the sound-board.

rlhe amplifying section proper comprises the parallel parts 12 and 13which are connected by the bend 14, 'there being a bend 15 at one end ofthe portion 13 which in turn connects to an elbow 16, as at 17. Theelbow 16 in turn connects at 18 to an outlet terminus 19 which hasconical or diverging walls to permit of the expansion of sound as itleaves the amplifier.

The tone arm section comprises an elbow 2O which is swivelly connectedat 21 to the sleeve 8, there being a semicircular bend 22 connected at23 to the elbow 20. This bend lies in a plane laterally to the elbow 20and is in turn connected at 24 to a straight section of tubing 25. Anelbow 26 is swivelly mounted at 27 in one end of the straight section25, so as to permit of vertical movements of the elbow which is in turnconnected at 28 to a straight section 29 of the tone arm.

Enf;

'lhis section 29 comprises two parts 30 and 3l which have adjacentflanged ends 32 clamped together by set-screws or the lile 33. Thesection 31 is capable of axial movement relative to the section andafter the section 3l has been adjusted, the set-screws or the like maybe tightened to hold the section 3l in position. ln other words,the'section 3l may be positioneo so as to hold the sound box 34 wherebyits stylus 35 may cooperate in the sound groove of the record, whichgroove causes vertical vibrations of the stylus. lt is possible toadjust the partA 3l so as to arrange the stylus to engage with the soundgroove ci? a record which causes lateral vibrations of the stylus. lineither case, the sound box is capable of accommodating itself to theirregularities el? the record through the medium ot' the swivel joint 27and the swivel joint-'28.

The part 3l of the straight section 29 is connected to an elbow 3G whichreceives the sleeve 37 of the sound box The sound box includes a rubbercap or sound deflector 38 which is fitted over the iace of the soundbox, covering the diaphragm, which deflects all the sound back throughthe tone arm which is continuous from the sound box to the outletterminus of the amplifier. y

`While the amplifier herein described is shown as comprising a speciednumber of sections,it is obvious that this number may be increased anyreasonable amount with correspondingincreased beneficial effects.

The invention having been set forth, what is claimed is:

In a talking machine amplifier, a tonearm, a sound box, a pair of elbowsconnecting the sound box' with the tone arm, one of said elbows having aswivel connection with the tone arm and thel othera swivel connectionwith the sound box, they adjacent ends of said elbows being providedwith flanges of which one is provided with diametrically disposedarcuate slots of approximately ninety degrees in length, and set screwsmounted in the flange of the other elbow and traversing the slots inrelative angular or turning movement of the two elbows.

In testimony whereof he aflixes his signaf ture. e

ANTHONY SEUFERT.

